The Epidemiology of the Comorbidity of Epilepsy in the General Population

PURPOSE: To describe the epidemiology of somatic and psychiatric conditions in adults with epilepsy in the community and compare it to that of people without epilepsy. METHODS: A cross-sectional population-based study extracting data from the UK General Practice Research Database for the period 1995-1998. Age- and sex-standardized prevalence rates were estimated for selected conditions and groups of conditions (categorized by ICD-9 chapters) in adults with epilepsy registered with primary care physicians. Results were compared with those in adults without epilepsy in the cohort, and prevalence ratios were calculated according to two broad age groups (16-64 and older than 64 years). RESULTS: Conditions common in the general population also were common in adults with epilepsy. Psychiatric disorders occurred twice as often, and the risk of somatic disorders was increased in people with epilepsy, with the exception of musculoskeletal and connective tissue disorders in older adults. The prevalence ratio of neoplasia, excluding intracranial tumors, was not increased in epilepsy. The prevalence ratio of brain tumors was particularly increased in young adults prevalence ratio (PR), 70.7 and of meningiomas in older adults (PR, 91.9). Neurodegenerative conditions, particularly dementias and Alzheimer' disease (PR, 6.3 and 8, respectively) and Parkinson' disease (PR, 3.2), appeared more frequently in people with epilepsy. Upper gastrointestinal bleed occurred more frequently in epilepsy (PR, 4.3), as did cardio- and cerebrovascular disorders, fractures, pneumonia and chronic lung diseases, and diabetes. Eczema, osteoarthritis, and rheumatoid arthritis did not occur more frequently in epilepsy. CONCLUSIONS: The prevalence ratio of many common psychiatric and somatic conditions is increased in adults with epilepsy who consult a primary care physician in the U.K. These findings may have implications in the diagnosis and management of epilepsy and coexisting conditions, as well as in health care provision.